NO.11 ABNORMAL SHIFTING


BHE050301026W16

11

Abnormal shifting

DESCRIPTION

• Shifts incorrectly (incorrect shift pattern).

POSSIBLE CAUSE

• Improper adjustment of TR switch
• Transmission fixed in 3GR (fail-safe function)
– Input/output signal malfunction (VSS, TCC solenoid, shift solenoids A, B, C and F)
• Maximum speed is low or acceleration is poor because 3GR is fixed as a fail-safe. In such a case, DTC is stored.
– Improper TCM ground
• Transmission is mechanically fixed in 3GR if TCM stops operating due to improper TCM ground. In such a case DTC is not stored.
• Clutch spillage
– In the event of clutch slippage, a DTC (incorrect gear ratio) is output.
• Control valve body malfunction (improper operation, stuck, clogged oil passage)
– Hydraulic circuit clogging (TCC solenoid, shift solenoids A, B, C and F)
– Control valve spool malfunction
• Torque converter malfunction (TCC piston is cracking or peeling.)
Note
• Before following the troubleshooting steps, make sure that the Automatic Transmission On-Board Diagnostic and Automatic Transmission Basic Inspection are conducted. (See BASIC INSPECTION.)

Diagnostic procedure

STEP

INSPECTION

ACTION

1
With the ignition switch at the ON position, does the gear position indicator light indication correspond to the selector lever position?
Yes
Go to the next step.
No
Go to No.29 "GEAR POSITION INDICATOR LIGHT DOES NOT ILLUMINATE IN M RANGE", or No.30 "GEAR POSITION INDICATOR LIGHT ILLUMINATES IN D RANGE OR P, N, R POSITIONS".
2
Disconnect the solenoid valve connector.
Does the vehicle operate as follows?
 

D range: 3GR (fixed)

R position: Reverse

Yes
Go to the next step.
No
Overhaul the control valve body and repair or replace any malfunctioning parts.
(See AT Workshop Manual.)
If the problem remains, overhaul the transmission and repair or replace any malfunctioning parts.
(See AT Workshop Manual.)
3
Drive the vehicle in D range.
Does the vehicle start from stop in the first gear?
Yes
Go to the next step.
No
Inspect the following values.
PCM PID (using WDS or equivalent):
• APP1
• APP2
• TR_REL
TCM terminal voltage:
• 2G (turbine sensor)
• 2K (VSS)
Repair or replace any malfunctioning parts.
4
Disconnect the TCM connector.
Is the resistance between terminal 2U at the TCM connector and terminal J at the solenoid valve wiring harness-side connector 5.0 ohms or less?
Yes
Go to the next step.
No
Repair open circuit.
5
Is the resistance between ground terminal 2M or 2Q at the TCM connector and body ground 5.0 ohms or less?
Yes
Go to the next step.
No
Repair open ground circuit.
6
Stop the engine.
Disconnect the solenoid valve connector.
Measure the resistance between the following solenoid valve connector terminals.
• Terminals E-J (shift solenoid A)
• Terminals F-J (shift solenoid B)
• Terminals H-J (shift solenoid C)
• Terminals I-J (shift solenoid F)
• Terminals G-J (TCC solenoid)
Are the resistances normal?
Yes
Go to the next step.
No
Inspect for open circuit in the malfunctioning solenoid and/or pressure switch related wiring harnesses.
• If the wiring harnesses are okay, inspect if the solenoids and/or pressure switch are stuck mechanically.
7
Remove the torque converter.
Inspect the torque converter.
(See AT Workshop Manual.)
Is the torque converter normal?
Yes
Overhaul the control valve body and repair or replace any malfunctioning parts.
(See AT Workshop Manual.)
If the problem remains, overhaul the transmission and repair or replace any malfunctioning parts.
(See AT Workshop Manual.)
No
Replace the torque converter.
8
Verify the test results.
• If normal, return to the diagnostic index to service any additional symptoms.
• If the malfunction remains, inspect the related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.
– If the vehicle is repaired, troubleshooting completed.
– If the vehicle is not repaired or additional diagnostic information is not available, replace the TCM.
(See TCM REMOVAL/INSTALLATION.)